APPENDIX. 



327 



Kiy;. 2">— Larva of 

 fourth series 

 just born from 

 wingless aiul 

 iisuniic female 

 of third series: 

 enlarged. 



the third series. It is certain that of the descendants of the second series a 

 considerable proportion become winged, but not nearly so many as in the 

 first series. There is no difference between the winged forms now maturing- 

 and those produced in May. 



The parthenogenetic wingless females of the third series are similar to 

 those of the second series, but the honey tubes are shorter, the tail is longer 

 and more slender, and it does not quite reach the same size. The antenna? 

 are six-jointed, there is a sensory pit at the end of the fifth joint, and a 

 group of four, all very distinct, is on the sixth joint. Day after day, until 

 June 13, these forms increased in number, and at that time those of the 

 second series had disappeared. It was hopeless now to attempt to follow out 

 individual series, and all that could be done was to recognize different types, 

 prevailing at different periods. It was not realized that 

 there was any notable difference except, possibly, in size, 

 otherwise it would have been easy to colonize individuals of 

 each brood upon other trees previously freed of all other 

 types. So it is not possible to speak delinilely of the length 

 of time required for an individual to come to maturity, but I 

 am inclined to believe that none develop so quickly as do 

 those of the second series. . In fact, judging from the pre- 

 served specimens and from the Held notes, new series ap- 

 peared at intervals of about twenty days. 



June 13, none of the second series remaining, the newly- 

 born larvae were all from the third series. They had short, 

 barrel-shaped honey tubes, four-jointed antenna? without sensory pits, and 

 did not offer other characters differentitlting them from previous forms. In 

 the second stage the honey tubes are equal to two body segments in length, 

 taper rather evenly to the tip, and are squarely cut off. The antenna? are 

 tive-jointed and there are no sensory pits. The third stage is somewhat 

 more oval, the honey tubes are yet stout and Hare a little at the tip. The 

 fourth stage was not identified with certainty. 



Winged forms began to decrease after June !•">, 

 though specimens occurred until about the middle of 

 July. On the seventeenth of that month no winged 

 forms could be found and no pupa?. It seems fairly 

 certain that the third series of wingless parthenogen- 

 etic females, maturing in early June, do not produce 

 winged forms, but only specimens similar to themselves- 

 Examinations were not made now so frequently as earlier 

 in the season, and specimens were preserved at inter- 

 vals- of from seven to ten days. A new series, the fourth 



Pier. 26 Second stase 



of "larva of fourfh of wingless breeders, was recognized on June 17. The 



series; enlarged, ^gney tubes are distinctly shorter than in any previous 

 series, the antennae are comi^aratively shorter, six-jointed, with a sensory 

 pit at the end of the fifth, and the tail is much longer in proportion than 

 ever before. 



No effort was made to obtain the early larva? from this series ; but 

 toward the end of the month the presence of a small oval type was recog- 



